| 摘要 |
The invention concerns a melting and casting means. The means comprises a heating chamber confined by side, top and bottom walls made of insulating material and enclosed by a steel shell. Mounted in the chamber are a crucible stand and upon said stand a crucible. According to the invention, the means further comprises at least three silicon carbide heating elements for heating the crucible to between 1100 DEG and 1650 DEG C. to the purpose of melting copper and copper alloys, and the insulating material mainly consists of aluminium oxide and silicon oxide fibres. The heating elements have been disposed in the chamber so that the distance between the element center and the outer wall of the crucible is 2 to 4 times the element diameter. The elements are advantageously disposed horizontally piercing the side walls of the means, and they have no contact with the bottom wall. The spacing of the heating elements from the inner wall of the chamber is advantageously 2 to 4 times the element diameter. The thermal conductivity of the thermally insulating material is about 0.1-0.3 kcal/m h DEG C. at 400 DEG C. and respectively 1200 DEG C. |
